In general, measurement for an electrocardiogram signal is made by an electrocardiogram monitor located in a hospital and a Holter electrocardiograph located out of the hospital. The electrocardiogram monitor located in the hospital employs a method of delivering an electrocardiogram signal to a central monitor located in the hospital via a wired or wireless local area network (LAN) and monitoring the electrocardiogram signal at the central monitor. The Holter electrocardiograph located out of the hospital is an apparatus for measuring an electrocardiogram for a subject who wears an electrocardiograph for 24 or 48 hours or longer, storing an abnormal signal, if it is detected, and analyzing the stored abnormal signal through a computer of the hospital visited by the subject in time.
With recent development of telecommunications technology, there have been developed techniques for transmitting an electrocardiogram signal to a remote place by wireless.
Examples of conventional techniques for transmitting an electrocardiogram signal or a bio-signal to a remote place by wireless include an ambulatory electrocardiograph, which is disclosed in Korean Patent Registration No. 10-0429823, and a real-time bio-signal monitoring system using a wireless communication network, which is disclosed in Korean Patent Registration No. 10-0197580.
The disclosed ambulatory electrocardiograph includes a typical electrocardiogram acquisition means with an abnormal signal decision algorithm contained therein, and interconnects a wireless communication device, a printer and a PCMCIA (Personal Memory Card International Association) and so on. In this electrocardiograph, if an abnormal signal occurs, an electrocardiogram signal is stored for a certain period of time before and after the occurrence of the abnormal signal and is transmitted to a remote hospital via a wireless communication network for a doctor's prescription.
The disclosed real-time bio-signal monitoring system using a wireless communication network checks bio-signal data and transmits an abnormal signal, if any, to a wireless relay station via an internal wireless modem. The wireless relay station transmits the abnormal signal to a bio-signal monitoring server of a hospital, and the bio-signal monitoring server monitors reception signals and transmits a measure and emergency prescription method corresponding to the monitored signal to a bio-signal holder apparatus.
The above conventional techniques relate to transmission of bio-signals to a remote monitoring server via a public wireless communication device incorporated in the electrocardiograph, wherein the bio-signals are consistently and automatically monitored and an abnormal signal is transmitted to a remote place only if it occurs. However, in case of intermittent arrhythmia or myocardial infarction, it has very short duration and its normal signal has substantially the same shape as its abnormal signal, thereby making automatic detection by a machine difficult. Further, it requires a complicated signal processing algorithm for the automatic detection. In addition, since it is common that an electrocardiogram is transmitted to a remote hospital rather than home, there is a need for a mobile device which can be freely moved in various regions such as in vehicles, mountains and so on.
In addition, the portable electrocardiograph need be convenient and simple in its measurement and usage while being compact and lightweight for portability.
However, if the portable electrocardiograph is installed with a complicated signal processing algorithm for real-time monitoring and transmission, it requires a high performance processor, which may result in great increase in system size and power consumption.
In other words, since the size of the portable electrocardiograph has direct relation with portability and power consumption also has direct relation with a battery size, it was very difficult to achieve a portable electrocardiograph for acquisition of electrocardiogram signals.